Clinicopathological and immunohistochemical study of 30 cases of post-radiation atypical vascular lesion of the breast

Abstract

Atypical vascular lesions (AVL) that occur in the field of prior radiation therapy for breast carcinoma are placed within the differential diagnosis with low grade angiosarcoma and other benign vascular lesions. Although considered a benign entity, the exact biological behavior of AVLs is not fully established because of the small number of cases reported in the literature. We aim to further characterize these lesions clinically and histopathologically, and to study their behavior. We report a series of 30 patients with AVL of the breast occurring after radiation exposure, diagnosed and treated at the European Institute of Oncology, Italy. Immunohistochemical study was performed in all cases, using CD31, D2-40, CD105, and Ki-67 antibodies. Twenty-seven patients were treated with standard doses of conventional adjuvant radiation therapy for the prior breast carcinoma. Three patients were treated with intraoperative radiotherapy with electrons. The post-radiation latency interval from breast carcinoma to AVL was 48.5 months (ranged from 1 to 146 months). Most of the lesions were classified as lymphatic type (78.6 %) based on D2-40 positivity. No extension into subcutaneous tissue or significant atypia was noted in all cases. Despite the fact that the AVL of our series have shown benign behavior in 93.3 %, one patient developed local recurrence of AVL, and two cases progressed to angiosarcoma at the previous AVL site. Further studies should be conducted to better understand the clinical behavior and to propose additional histopathologic diagnostic criteria to distinguish AVL from low grade angiosarcoma and those AVL with increased risk for malignant progression. Concerning current treatments of AVL, we recommend complete excision with free surgical margins and close follow up.

Angiosarcoma and atypical vascular lesions of the breast: diagnostic and prognostic role of MYC gene amplification and protein expression

“…Patient of case 23 developed a bilateral high-grade epithelioid AS 89 months after the initial diagnosis of AVL in the previous punch biopsy site. Details of these cases were previously described [11]. Both at diagnosis of AVL, as at the time of diagnosis of AS, no MYC amplification and protein overexpression were observed.…”

“…1a), but one patient was excluded from this study because there was no more representative tumor block available for MYC analysis. Clinicopathological details of these patients with AVL were published previously [11]. The main method used for the pathological diagnosis of AS was core biopsy (92 % of cases), and for diagnosis of AVL was punch biopsy (50 % of cases), followed by excisional biopsy.…”

“…The differential diagnosis between AVL and low-grade angiosarcoma (AS) can be occasionally very difficult or even impossible, mostly in small-sized skin biopsies, due to the histologic overlap characteristics between low-grade AS and AVL [5,10]. Some studies reported patients with AVL who later developed AS, suggesting that AVL may be a precursor to or an incipient angiosarcoma [6,7,11].…”

“…As accurate morphological diagnosis between low-grade AS and AVL can be difficult and the utility of immunohistochemical (IHC) stains for this particular diagnostic dilemma has not been established [11], new methods to distinguish these two biologic entities are a welcome tool in the clinical setting.…”

Early Onset Post-Radiation Cutaneous Angiosarcoma of the Breast with Features of Atypical-Vascular Lesion: A Diagnostic Pitfall and Its Biologic Significance

“…AVLs have been classified as lymphatic or vascular types principally on the basis of immunophenotype, with the lymphatic-type AVLs (ltAVL) representing the majority, and expressing D240 [9]. In a large series, those with a lymphatic phenotype behaved less aggressively than those with a vascular phenotype [7].…”